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Re: Focus!!



>Hi guys,
>I have a question I hope someone can answer.
>In a recent session on URSA Gold, using the Super 16 gate, I noticed that
>the focus was looking soft........deletia......


Mark,
There is an easy trick to get focus optimized.  (Let's assume the film path
is aligned properly and is seated properly in the gate so it's not changing
it's position between Run and Still).  Some gates have curved skid plates
which will have a different focal point at the image top and bottom than in
center since the lenses are designed to focus on a flat field.  When the
machine is in Run mode the raster becomes a lot smaller in the Vertical
Scan direction so the focal point of the center (in the top to bottom
direction) becomes the focal point for the entire image.  If you focus the
gate in Still mode, use the 15 line Strobe feature of your bridge waveform
monitor/Pix monitor combination to select the central part of the image.
Adjust focus using the scope to look for maximum detail in the selected
central area. Some people put the scope in 3.58 or 4.43 MHz bandpass mode
at high gain to exaggerate the detail display. This technique should then
also give you best focus in Run mode.

Dave Corbitt
Manhattan Transfer / Edit, Inc.
NYC


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